NSPredicate的在查询中的简单使用

来源:互联网 发布:找不到男朋友 知乎 编辑:程序博客网 时间:2024/06/16 06:27

上代码吧,每块代码都可以直接跑,并附有注释和运行结果

//直接使用 == 严格匹配NSArray *arrOriginal = [NSArray arrayWithObjects:@"c1",@"c", @"cd", @"cdd", @"cd", nil];NSString *match = @"cd";NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF == %@", match];NSArray *results = [arrOriginal filteredArrayUsingPredicate:predicate];NSLog(@"result===%@",results);

打印结果:
result===(
cd,
cd
)

//like匹配,类似Sql中的用法NSArray *arrOriginal = [NSArray arrayWithObjects:@"c1",@"d", @"cd", @"cdd", @"dd",@"dcd",@"cdc", nil];NSString *match = @"c*";//以c开头NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF like %@", match];NSArray *results = [arrOriginal filteredArrayUsingPredicate:predicate];NSLog(@"result===%@",results);

打印结果:
result===(
c1,
cd,
cdd,
cdc
)

//忽略大小写进行匹配NSArray *arrOriginal = [NSArray arrayWithObjects:@"Cdd",@"cDc",@"cdd",@"dcdd", nil];NSString *match = @"cd*";NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF like[c] %@", match];NSArray *results = [arrOriginal filteredArrayUsingPredicate:predicate];NSLog(@"result===%@",results);

打印结果:
result===(
Cdd,
cDc,
cdd
)

//利用正则表达是进行过滤NSArray *arrOriginal = [NSArray arrayWithObjects:@"c1",@"C3",@"d2",@"c2", nil];NSString *match = @"^c\\d?";NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF matches %@", match];NSArray *results = [arrOriginal filteredArrayUsingPredicate:predicate];NSLog(@"result===%@",results);

打印结果:
result===(
c1,
c2
)

//利用过滤器(数组)进行过滤NSArray *arrFilter = [NSArray arrayWithObjects:@"aa", @"bb", nil];NSArray *arrOriginal = [NSArray arrayWithObjects:@"dds",@"bb",@"c1",@"C3",@"bb",@"aa",@"c2", nil];NSPredicate *predicate  = [NSPredicate predicateWithFormat:@"NOT (SELF in %@)", arrFilter];//不包含符合过滤器的内容NSArray *results = [arrOriginal filteredArrayUsingPredicate:predicate];NSLog(@"result===%@",results);

打印结果:
result===(
dds,
c1,
C3,
c2
)


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